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' M. K. KENDALL.

ELEGTRIGAL RAIL'BOND.

No. 552,479. Patented Dec. 31,1895.

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- M. K. KENDALL.

ELECTRICAL RAIL BOND. N0. 552,479. Patented 1360.31, 1895.

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MINOTT K. KENDALL, OF MELROSE, ASSIGNOR OF TVVO-THIRDS TO GILBERT I'IODGES, OF MEDFORD, AND EPHRIAM HARRINGTON, OF BOSTON, MASSA- CHUSETTS.

ELECTRICAL RAIL-BOND.

SPECIFICATION forming part of Letters Patent No. 552,479, dated December 31, 1895.

Application filed August 12, 1895. $erial No. 559,050. (No model.)

To all whom it may concern.-

Be it known that I, MINoTr K. KENDALL, of Melrose, in the county of Middlesex and State of Massachusetts, have invented certain new and useful Improvements in Electrical Rail-Bonds, of which the following is a specification.

This invention has relation to bonds for electric railways, and has for its object the provision of a bond which shall be a highly efficient electrical conductor, and which shall be so connected electrically with the rails as to offer the least possible resistance to the currents of electricity.

A further object of the invention is the provision of a bond which can be produced and applied at the least expense, and which can be used in connection with railways as they are now constructed without requiring special attachments or constructions.

My invention consists in forming a series of cross-slits in the bond, placing the bond with the center of the cross-slits opposite bolt-holes in the web of the rail, and driving a bolt or pin into thebolt-hole, which forces the points or projections formed by the slits into the bolt-hole and tightly wedges them between the web and the bolt.

Reference is to be had to the annexed drawings, and to the letters marked thereon, forming a part of this specification, the same letters designating the same parts or features, as the case may be, wherever they occur.

In the drawings, Figure 1 is a perspective view of two meeting rails with angle-irons, showing how the bond is secured in place between them. Fig. 2 is a perspective view of one of the angle-irons with the bond removed from the rails. Fig. 3 is a cross section through one of the bolts, showing how the metal of the bond is upset and forced into the bolt-hole in the rail. Fig. 4 is a crosssection of the rail, the angle-iron, and the bond at a point intermediate of two of the bolts. Figs. 5 and 6 are views from opposite sides of the bond. Fig. 7 is a cross-section of a modified bond.

The two rails which it is desired to electrically connect are designated by A and B, each having a web a, a baseflange a and a tread a as is customary in rails of this character which are used in electric-railway systems. The rails are connected and braced by the angle-irons or fish-plates I), each of which has an upright portion with an inwardly-projecting flange fitting under the tread a of the rail, and has an inclined base fitting over the base-flange of. In the space between the Web of the rail and the upright flange of the fishplate or angle-iron I place the bond 0, it being formed of a straight strip of copper having a flat face 0, which is placed against the web of the rail. Its other face is provided with thickened portions c at intervals, which are designed to be pressed against by the inner surface of the upright portion of the fishplate to hold the surface 0 against the rail. These are arranged between the bolts d which pass through the fish-plates, the web of the rail, and the bond to bind them firmly together, the metal of the bond being, in the process of binding the parts together, crushed and bent to a certain extent, so as to effect a complete matching or fitting of the parts.

In order to insure a perfect contact between the bond and the rail, I make a series of crossslits e in the bond in the form of a star, as shown, instead of cutting out round apertures to pass the bolts cl through, and then I force the bolt throughthe metal, as at e, and force the triangular points or projections thus formed into the aperture a in the web of the rail, which is slightly enlarged as usual to provide for expansion and contraction in rails due to variations of temperature.

In Fig. 6 I have illustrated by dotted lines how the end of the copper bonds maybe drawn or spun out into a wire for connecting a conducting-wire thereto.

In Fig. '7 a modified form of bond is shown in which the projection or collar 6 which surrounds the bolt-hole a is sweated, brazed or otherwise secured to the bond, and is wedged between the bolt and the rail, as above described.

By wedging, as itwere, the bolts in the bolt-holes of the web of the rail perfect electrical contact is secured, and at the same time the bolts are maintained against turning, so as to obviate the necessity of employing nut-locks on the bolts. In this respect the invention serves the double purpose of an electric bond and a nut-lock.

Again, by the invention a bond is provided with an approximately maximum carrying capacity and approximately minimum electrical resisting properties, so that very mate rial relief is afforded to the usual return-wires, which is a matter of material importance, as is well known to those skilled in the art.

It is to be observed that the invention is so constructed as that it may be applied to railway-rails in connection with the usual angleirons or fish-plates without modifying the construction of either in the slightest degree, and without making any additional holes in the web or other parts of the rail, and without making the usual holes of different size or form.

In drawing or turning up the nuts on the bolts the metal of which the bond is composed, being comparatively soft and malleable, will be bent and crushed so as to conform to the form of the adjacent parts and surfaces of the web of the rail an d angle-iron or fish-plate, and so form quite as complete and perfect an electrical contact between the bond and rail as though the two parts were integral.

A bond thus constructed and related to the rail has been ascertained by actual experiment to possess electrical carrying capacity equal to any that may be required in electrical railways, and to have exceedingly low electrical resisting properties, ends most desirable to be attained in devices of the character to which this invention appertains,

Having thus explained the nature of the invention and described a way of constructing and using the same, though without attempting to set forth all of the forms in which it may be made or all of the modes of its use, it is declared that what is claimed is 1. An electrical bond for railway rails comprising in its construction, a strip of metal of electrical conductivity, adapted to be placed against the side of the web of the rail, the side remote from the web of the rail having thickened portions, 0 and the said strips being provided with bolt holes and a projection surrounding each hole, said projection being adapted to enter the bolt holes in the web of the rail and to be snugly wedged therein by the bolt.

2. An electrical bond for railway rails, comprising in its construction a strip of conductor metal provided with cross slits which form points or p'rojections adapted to be forced into a bolt hole in the web of the rail, and tightly wedged therein by the bolt.

In testimony whereof I have signed my name to this specification, in the presence of two subscribing witnesses, this 3d day of August, A. D. 1895.

MINOTT K. KENDALL. \Vitnesses:

ARTHUR \V. CRossLEv, (J. C. STEOHER. 

